JPH1190980A - Manufacture of bent hose - Google Patents

Abstract

PROBLEM TO BE SOLVED: To protect the sectional shape of a bent hose from being deformed into the ellipse shape or deformed into the bent shape different from the set shape on a bent section in a manufacturing method in which the unvulcanized rubber hose is inserted along a forming channel section of an outer shape and set thereon and vulcanization molded in the state of being kept and restrained in the bent shape. SOLUTION: An unvulcanized rubber hose 10A is inserted into a diameter section through its opening section 40 along a forming channel section 24 on an outer mold 22 and set therein, and vulcanized in the state of being kept and restrained in the bending shape. At that time, a press cover 42 with a press face 43 facing a bottom face of the forming channel section 24 is brought into contact with an exposed section on the opening section 40 of the unvulcanized rubber hose 10A inserted and set on the outer mold 22, and the vulcanized rubber hose 10A is vulcanized while controlling the deformation in the ejection direction of the forming channel section 24.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a curved hose, and more particularly, to a method for vulcanizing an unvulcanized rubber hose using an outer mold (which may have a reinforcing layer or a resin layer, but is particularly based on rubber). The present invention relates to a method of performing a sulfurizing treatment.

[0002]

2. Description of the Related Art Conventionally, as a method of manufacturing a curved hose having a predetermined bent portion, a completely unvulcanized rubber hose (hereinafter, a completely unvulcanized rubber hose and a semi-vulcanized rubber hose formed into a straight tube by extrusion molding or the like) is used. Insert a mandrel that has been deformed into a round bar shape and a predetermined bent shape made of iron into the hollow interior of the uncured rubber hose (collectively referred to as an unvulcanized rubber hose), and deform the unvulcanized rubber hose into a shape that follows the mandrel. A method of heating and vulcanizing an unvulcanized rubber hose while holding it has been generally used.

FIG. 13 shows this concretely. In the figure, reference numeral 200 denotes a mandrel which has been deformed into a predetermined bent shape. In this method, a release agent is generally applied to the surface of the mandrel 200 (I), and the mandrel 200 is inserted into the straight tubular unvulcanized rubber hose 202 while bending and deforming the hose (II). Unvulcanized rubber hose 202 and mandrel 200
Together to vulcanize the unvulcanized rubber hose 202
(III). Thereafter, the mandrel 200 is removed from the curved hose 204 after vulcanization (IV), and the release agent remaining on the inner surface of the mandrel 200 and the product hose (curved hose) 204 is washed and removed ((V), (VI)). ).

However, in the case of the conventional manufacturing method using such a mandrel 200, the frictional force between the mandrel 200 and the unvulcanized rubber hose 202 or the curved hose 204 after vulcanization, particularly a large resistance force at the bent portion. Therefore, when the mandrel 200 is inserted into the unvulcanized rubber hose 202 and when the mandrel 200 is removed from the curved hose 204 after vulcanization, the mandrel 200 must be performed with a strong force. It was a difficult task.

In recent years, as shown in FIG. 14, an outer mold 208 having a molding groove 206 having a predetermined curved shape is used, and a straight tubular unvulcanized rubber hose 202 is formed along the molding groove 206 of the outer mold 208. A method has been considered in which the hose is set in a radial direction and vulcanized in that state to obtain a curved hose.

According to this manufacturing method, the straight tubular unvulcanized rubber hose 202 can be fitted and set in the outer mold 208 with a relatively small force, and the curved hose can be taken out of the outer mold 208 even after vulcanization. There is an advantage that work can be performed easily.

In addition, in the case of this manufacturing method, since a mandrel is not used, it is not particularly necessary to apply a release agent. Therefore, not only the step of washing and removing the release agent after vulcanization can be made unnecessary, but also the release The advantage is obtained that it is possible to avoid the problem that the agent and the detergent for removing the agent enter the waste liquid and the water treatment for improving the water quality becomes difficult.

[0008]

The outer mold 20
In the conventional method using the molding groove 8, the molding groove 20 is usually used.
Form 6 has the following form, that is, has a groove side surface along the inner peripheral side and the outer peripheral side of the bent portion, and an opening is formed between them that extends continuously along the longitudinal direction of the forming groove. In this case, the forming groove 2 is formed through the opening.
When an unvulcanized rubber hose is inserted and set in 06 and vulcanized, as shown in FIG. 14 (B), the hose buckles or has a flattened cross section (elliptical shape) at the bent portion. Inherent problems such as

That is, in the case of this manufacturing method, since the shape of the unvulcanized rubber hose is not regulated from the inner surface side by using the mandrel, there arises a problem that the hose is deformed in a direction protruding from the molding groove at the bent portion. This tendency tends to occur particularly when the hose diameter is large and the radius of curvature of the bent portion is small, that is, when the bent portion is bent at a sharp angle.

[0010]

The invention of the present application has been made to solve such a problem. According to a first aspect of the present invention, there is provided a method of manufacturing a curved hose, comprising forming an unvulcanized rubber hose along the formed groove of an outer mold having a bent groove having a bent portion corresponding to a bent hose product. In the method for manufacturing a curved hose in which the unvulcanized rubber hose is vulcanized while being held and constrained in a bent shape by being fitted and set in a radial direction through the opening of the groove, the outer groove is formed as the outer die. It is characterized in that at least a part of the bent portion has the opening along the inner peripheral side and has a groove bottom along the outer peripheral side.

According to a second aspect of the present invention, there is provided a method for manufacturing an unvulcanized rubber hose along a molding groove of an outer mold having a curved molding groove having a curved portion corresponding to a curved hose product. In a method for manufacturing a curved hose in which the unvulcanized rubber hose is set in a radial direction through an opening of the groove and vulcanized while the unvulcanized rubber hose is held and restrained in a bent shape, a presser opposed to a bottom surface of the molding groove is provided. A pressing lid having a surface is applied to the exposed portion of the opening of the molding groove of the curved portion of the unvulcanized rubber hose fitted and set in the outer mold, and the deformation of the curved portion in the direction of protrusion from the molding groove is reduced. It is characterized in that the unvulcanized rubber hose is vulcanized while restraining.

According to a third aspect of the present invention, there is provided the method for manufacturing a curved hose according to the second aspect, wherein the molding groove has a first and a second curved portion corresponding to the curved hose product as the outer mold. And the first and second bends are bent in different planes forming a predetermined angle, and the forming groove is formed as a three-dimensional bend as a whole. Wherein the unvulcanized rubber hose is vulcanized using the holding lid.

According to a fourth aspect of the present invention, in the method for manufacturing a curved hose according to any one of the first to third aspects, the groove depth of the molding groove is larger than the radius of the unvulcanized rubber hose, and the opening of the molding groove is formed. The width of the opening of the portion is substantially equal to the diameter of the unvulcanized rubber hose.

According to a fifth aspect of the present invention, there is provided a method of manufacturing a curved hose, wherein an unvulcanized rubber hose is set in a molded concave portion of an outer mold and held and restrained in a bent shape having a predetermined bent portion. In the method for manufacturing a curved hose to be applied, an outer mold having a curved shape corresponding to the bent portion and comprising a cylindrical pipe for partially restraining the bent portion in a longitudinal direction is used as the outer mold. A part of the unvulcanized rubber hose in the longitudinal direction is held and restrained in a curved shape by inserting the vulcanized rubber in the axial direction through the outer mold, and vulcanization is performed in that state.

[0015]

As described above, according to the manufacturing method of the first aspect, at least a part of the molding groove has an opening along the inner peripheral side of the bent portion as the outer mold, and the outer peripheral side has the opening along the outer peripheral side. According to this manufacturing method, even if the unvulcanized rubber hose tries to buckle or make an elliptical shape at the bent portion, the bent portion is formed by a pair of groove side surfaces in the major axis direction of the ellipse. Since the unvulcanized rubber hose is restrained in the (long-axis direction), it is effectively prevented that the unvulcanized rubber hose is buckled or flattened (elliptically shaped) at the bent portion. Therefore, according to the manufacturing method of the first aspect, a curved hose having a good sectional shape can be obtained.

According to a second aspect of the present invention, a pressing lid having a pressing surface opposed to the bottom surface of the forming groove is used, and the pressing surface is formed at the exposed portion of the opening of the forming groove in the bent portion of the unvulcanized rubber hose. To vulcanize the unvulcanized rubber hose while suppressing deformation in the direction of protrusion from the molding groove.
Also in this manufacturing method, it is possible to effectively prevent the unvulcanized rubber hose from buckling at the bent portion or from being flattened into a cross-sectional shape such as an elliptical shape.

In the case of the method according to the second aspect, the molded groove portion has any of the following forms, that is, has a groove side surface along the inner peripheral side and the outer peripheral side of the bent portion, An opening along the inner circumferential side like the forming groove in the manufacturing method according to claim 1, even if the part between them is a forming groove having a continuous opening in the longitudinal direction of the forming groove. Even if it is a molded groove portion having a groove bottom surface along the outer peripheral side, there is a feature that the unvulcanized rubber hose can be reliably prevented from being deformed in the bent portion in the direction protruding from the molded groove portion.

As described above, when the forming groove portion has an opening along the inner peripheral side of the bent portion and has a groove bottom surface along the outer peripheral side, the cross-sectional shape of the bent portion is flattened. Can be suppressed well, but when the hose shrinks in the longitudinal direction during vulcanization, the bent part deforms in the direction protruding from the molding groove, that is, the bent part emerges from the molding groove to the outside through the opening The phenomenon of deformation in the direction cannot be sufficiently prevented. When such a phenomenon occurs, the bent shape at the bent portion is different from the set shape. However, according to the manufacturing method of the second aspect, such a phenomenon can be surely suppressed.

According to a second aspect of the present invention, there is provided a method for manufacturing a three-dimensionally bent hose using the same outer mold, that is, a case where the molding groove has a three-dimensionally bent shape as a whole. This is particularly effective when applied to (3).

In the case of a three-dimensional bend having a plurality of bends and the bends in different planes forming a predetermined angle, the position of the opening in the forming groove for each bend It is practically difficult to make the directions different from each other, and in this case, when the three-dimensional curved hose is vulcanized and formed according to the manufacturing method of claim 2,
Irrespective of the shape of the forming groove and the orientation of the opening, it is possible to reliably prevent the bent portion of the hose from being deformed in the direction protruding from the forming groove.

That is, when the manufacturing method according to the second aspect is applied to the manufacture of a three-dimensionally curved hose, the flattening of the cross-sectional shape at the bent portion and the floating from the molding groove portion due to shrinkage of rubber during vulcanization. Any problem of the out-form can be solved.

It is desirable that the molding groove has a groove depth larger than the radius of the unvulcanized rubber hose and the opening width of the opening is substantially equal to the diameter of the unvulcanized rubber hose. With this configuration, the unvulcanized rubber hose can be stably held and restrained in the bent shape at the molding groove.

Accordingly, it is not necessary to form the outer mold into a split mold structure and to wrap and hold and restrain the entire outer peripheral surface of the unvulcanized rubber hose by each split mold, thereby simplifying the structure of the outer mold.

In this case, at least a pair of groove side surfaces extending from a groove depth corresponding to a radius of the unvulcanized rubber hose to the opening is a straight surface extending while maintaining substantially the same groove width as the opening. Can be.

According to a fifth aspect of the present invention, there is provided the manufacturing method as described above,
In the method, an unvulcanized rubber hose is used that is formed of a cylindrical pipe that is continuous in the circumferential direction and partially constrains the bent portion of the unvulcanized rubber hose in the longitudinal direction. The problem of deformation in the protruding direction can be solved.

Further, since the outer mold partially restrains the unvulcanized rubber hose in the longitudinal direction, the operation of inserting the unvulcanized rubber hose in the inside thereof in the axial direction can be easily performed.

[0027]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing an embodiment of the present invention; FIG. 1 shows an example of a curved hose to which the present invention is applied. As shown in FIG. 1, this curved hose 10 has a first bent portion 12, a second bent portion 14, and both ends. It comprises a straight portion 16, 18 and a straight portion 20 between the bent portions 12, 14. Here, the first bent portion 12 and the second bent portion 14 each have a two-dimensional bent shape on different planes forming a predetermined angle with each other, and the bent hose 10 has a three-dimensional bent shape as a whole. I have.

FIG. 2 shows the outer mold 22 and the holding lid 42 used when vulcanizing the curved hose 10. In the same figure, reference numeral 24 denotes a molding groove provided in the outer mold 22, and molding parts 26, 28 corresponding to the first bent part 12, the second bent part 14, and the straight parts 16, 18, 20 of the curved hose 10, respectively. , 30, 32 and 34.

As shown in FIG. 3B, the molding groove 24 has a U-shaped cross section. For more information,
The portion from the groove bottom surface 36 to the lower portion of the groove side surface 38 has a semicircular cross section, and the upper portion of the groove side surface 38 forms a vertical straight surface, reaching the opening 40 at the upper end.

Here, the diameter of the semicircular portion in the cross section is
The outer diameter D of the unvulcanized rubber hose 10A is substantially the same as the outer diameter D of the unvulcanized rubber hose 10A, and the groove width between the pair of groove side surfaces 38 and the opening width of the opening 40 are both the outer diameter of the unvulcanized rubber hose 10A. The groove width and the opening width are substantially the same as D. still,
The groove depth H of the molding groove portion 24 is made deeper than the radius of the unvulcanized rubber hose 10A. Specifically, in the case of this example, the groove depth H is set to a groove depth of about 4/5 of the diameter of the unvulcanized rubber hose 10A, that is, the curved hose 10.

As shown in FIG. 2, the shape of the forming portion 26 for forming the first bent portion 12 of the bent hose 10 is formed along the inner peripheral side and the outer peripheral side of the bent portion. And has a groove side surface 38 and an opening 40 therebetween. The shape of the forming portion 28 for forming the second bent portion 14 is a shape having a groove bottom surface 36 along the outer peripheral side of the bent portion and an opening 40 along the inner peripheral side.

In FIG. 2, reference numeral 42 denotes a holding lid, which has a plate shape and has a three-dimensional curved shape corresponding to the forming groove 24. That is, the holding lid 42 is formed by the forming portions 26 and 28 and the forming portions 30 and 3 in the forming groove portion 24.
Holders 44, 46, 48, 50, 5 corresponding to 2, 34
Two. The lower surface of the holding lid 42 is
4, a pressing surface facing the groove bottom surface 36;
6, 28 and a pressing surface 43 facing the groove bottom surface 36 of each of the molded portions 30, 32, 34.

In this example, the holding surface 43 is
, That is, a flat surface in the direction perpendicular to the longitudinal direction of the forming groove 24. The outer mold 22 and the holding lid 42 can be made of silicone rubber. Of course, other materials such as metal can be used.

A vulcanized curved hose 1 is provided on the surface of the outer mold 22 on the opening 40 side and at each longitudinal end of the molding groove 24.
An inspection mark 54 for inspecting and confirming the length of 0 can be provided. In this case, when the curved hose 10 is taken out of the outer mold 22 after vulcanization, the length thereof can be inspected at the same time.

That is, conventionally, as shown in FIG. 11, after the curved hose 10 is removed from the mandrel or the outer mold after vulcanization, the curved hose 10 is inserted into a separately prepared inspection mold 210. In this example, it was inspected whether or not the curved hose 204 had an appropriate length by using the inspection mark 54 provided on the inspection mold 210 so that the curved hose 204 was set along the inspection mold 210. According to the method described above, such a separate mold 210 and an inspection process are not required,
When taking out the curved hose 10 from the outer mold 22, the length can be confirmed at the same time.

FIG. 5 shows a method of manufacturing the curved hose 10 of the present embodiment using the outer mold 22 and the presser lid 42. As shown in the drawing, in the manufacturing method of the present embodiment, first, extrusion molding and thereafter, A straight tubular unvulcanized rubber hose 10A is obtained by cutting or the like having a predetermined dimension, and the straight tubular unvulcanized rubber hose 10A is bent and deformed along the forming groove 24 of the outer mold 22 to form the forming groove 24. The fitting is set in the radial direction through the opening 40 (FIG. 5I).

After the unvulcanized rubber hose 10A has been fitted into the molding groove 24, the holding lid 42 is set, and the holding surface 43 protrudes from the top of the unvulcanized rubber hose 10A, that is, the opening 40 of the molding groove 24. It is in a state of contacting the top of the part. Then, in that state, the unvulcanized rubber hose 10
A, the outer mold 22, and the presser cover 42 are inserted into the vulcanization chamber, and the heat vulcanization is performed for a predetermined time (FIG. 5 (II)).

At this time, as shown in FIGS. 3 and 4, the holding lid 42 is in contact with the unvulcanized rubber hose 10A over the entire length of the forming groove 24 including the forming portions 26 and 28, and Since the projecting deformation from the groove 24 is prevented, the unvulcanized rubber hose 10
A is vulcanized and formed into a desired cross-sectional shape and bent shape.

That is, as shown in the comparative example of FIG. 12, when the vulcanization treatment is performed using only the outer mold 22 without using the holding lid 42, it is shown in FIG. As described above, the unvulcanized rubber hose 10A is deformed in the protruding direction from the molding groove 24 in the molding portion 26, and the cross-sectional shape becomes elliptical. Although the cross-sectional shape does not change to an elliptical shape in the molding portion 28, the curved hose 10 rises up from the molding groove portion 24 due to shrinkage during vulcanization, as shown in FIG. This causes a problem that the bent shape becomes different from the set bent shape.

However, according to the manufacturing method of this embodiment shown in FIG. 5, such a problem does not occur in any of the molded portions 26 and 28, and the curved hose 10 can be satisfactorily added to a desired sectional shape and curved shape. It can be vulcanized.

When the heat vulcanization treatment is completed as described above, they are taken out of the vulcanization chamber as shown in FIG. 5 (III), the holding lid 42 is removed, and the vulcanization after vulcanization is further performed. The curved hose 10 is removed from the outer mold 22. Here, a curved hose 10 having a desired curved shape can be obtained.

According to the manufacturing method of the present embodiment, when the unvulcanized rubber hose 10A is going to be formed into an elliptical shape in the molding portion 28 of the outer mold 22, the unvulcanized rubber hose 10A is formed into a pair of groove side surfaces 38 in the molding portion 28. As a result, the unvulcanized rubber hose 10 </ b> A is prevented from being formed into an elliptical shape in the elliptical direction (long axis direction). Therefore, the second bent portion 14 of the curved hose 10 is formed into a good cross-sectional shape. Furthermore, the action of the holding lid 42 prevents the hose from rising and deforming from the molding groove 24 due to shrinkage during vulcanization in the molding section 28.

On the other hand, in the molding portion 26, the hose is not lifted and deformed from the molding groove 24 due to such shrinkage at the time of vulcanization. However, in the same portion, the cross-sectional shape of the hose tends to be elliptical. I do. However, in this example, since the holding lid 42 prevents the deformation, the flattening of the cross section is prevented. That is, according to the manufacturing method of the present embodiment, when the three-dimensional curved hose 10 is vulcanized and molded by using the outer mold 22, the problem of flattening of the cross-sectional shape and the irregularity of the curved shape due to the shrinkage of the rubber. No problem arises.

FIG. 6 shows another embodiment of the present invention. This example is an example in which the holding lid 42 has a different form from the above example. Specifically, the holding lid 42 is formed by a first layer 56 made of a metal plate and a second layer 58 made of silicone rubber. And a pressing surface 60 having an arc-shaped cross section is formed on the second layer 58 made of silicone rubber. The pressing surface 60 is also formed continuously along the forming groove 24 of the outer die 22 in this example.

Here, the second layer 58 of the holding lid 42 made of silicone rubber can be easily formed as follows. That is, as shown in FIG. 7, a male mold 62 having the same shape as the curved hose 10 is fitted and set in the molding groove 24 of the outer mold 22, and a gap between the male mold 62 and the molding groove 24 is formed. As shown in FIG. 7 (II), the side frame 66 is erected, and the side frame 66 and the outer mold 22 constitute a mold 68, and a fluid state is formed inside the mold 68. The (uncured) silicone rubber material is poured and a curing reaction is performed to develop elasticity (FIG. 7 (III), FIG. 8)
(IV)).

Thereafter, as shown in FIG. 8 (V), the silicone rubber molded body which has undergone the curing reaction is released from the mold to form the second layer 58, which is formed of the first layer 56 made of a metal plate.
The cover lid 42 shown in FIG.
I)).

FIG. 9 shows still another embodiment of the holding lid 42. In this embodiment, the holding lid 42 made of silicone rubber or the like is provided with a downward projecting portion 70, and the projecting portion 7 is provided.
0 has an arc-shaped pressing surface 72 formed thereon. still,
Also in this example, the protruding portion 70 and the pressing surface 72 are formed continuously in the longitudinal direction along the forming groove 24.

FIG. 9B shows still another embodiment of the holding lid 42. In this embodiment, a projection 70 and a holding surface 72 are shown.
A second layer 58 comprising a metal plate
6 is an example in which the cover lid 42 is laminated and fixed to form a holding lid 42.

FIG. 10 (A) shows an outer die used in another embodiment of the present invention. This outer die 74 is formed by cutting out a part of the pipe material in the circumferential direction continuously in the longitudinal direction. The outer mold 74 is formed by pushing and expanding the vicinity of the notch in the widening direction and having the curved groove 24 having a U-shaped cross section and a curved shape corresponding to the curved hose 76. By using such an outer mold 74, a curved hose 76 having a predetermined curved shape can be obtained.

In the case of the outer die 74 shown in FIG. 10A, the opening 40 extends along the inner peripheral side of the bent portion 80 and the groove bottom 36.
Are formed along the outer peripheral side, so that the cross-sectional shape of the curved hose 76 at the bent portion 80 can be prevented from being made elliptical. The outer mold 74 can also be formed by bending a plate.

FIG. 10B shows an example of an outer die used in another embodiment of the present invention. In this example, an outer die 78 is formed by connecting a pipe of a predetermined length to a bent portion 80 of a curved hose 82. And an outer mold 78 that partially restrains the bent portion 80 in the longitudinal direction.

Here, the molding concave portion 84 inside the outer mold 78 has a circular cross section having an outer diameter substantially the same as the outer diameter of the curved hose 82, and is used for vulcanizing the unvulcanized rubber hose 10A. The bent portion 80 is held and restrained in a bent shape over the entire outer peripheral surface.

In this method, the unvulcanized rubber hose 1
The problem that OA is deformed in the direction protruding from the molding groove 24 at the bent portion 80 can be solved.

The outer mold 78 is made of an unvulcanized rubber hose 10.
Since A is partially restrained in the longitudinal direction,
The work of inserting the unvulcanized rubber hose 10A into the inside can also be easily performed.

Although the embodiment of the present invention has been described in detail, this is merely an example. For example, in the above embodiment, it is desirable that the portion of the holding lid 42 that abuts on the unvulcanized rubber hose 10A is softer than the unvulcanized rubber hose 10A, but a harder one may be used in some cases. In some cases, the presser lid 42 may be partially used only in the bent portion.

Further, in the above-described embodiment, all of the forming grooves 24 are formed to be continuous in the longitudinal direction, but may be discontinuous in the longitudinal direction in some cases. In short, any material can be used as long as it can hold and constrain the unvulcanized rubber hose 10A in the final bent shape.

Further, in the embodiment shown in FIG.
The present invention can be configured in a form in which various changes are made without departing from the gist of the invention, such that the outer mold 74 having the opening 40 can be configured as a partial mold that partially holds and restrains the bent portion 80. It is feasible.

[Brief description of the drawings]

FIG. 1 is a diagram showing an example of a curved hose to which the present invention is applied.

FIG. 2 is a view showing an outer mold and a holding lid used in a method of manufacturing the curved hose of FIG. 1 according to an embodiment of the present invention;

FIG. 3 is an external view and a cross-sectional view of a main part in a state where an unvulcanized rubber hose and a holding lid are set on the outer mold of FIG. 2;

FIG. 4 is a sectional view of a main part of FIG. 3 (A).

FIG. 5 is an explanatory view of a method of manufacturing the curved hose of FIG. 1 using the outer mold and the holding lid of FIG. 2 according to an embodiment of the present invention.

FIG. 6 is a sectional view showing a holding lid used in another embodiment of the present invention together with an outer mold.

FIG. 7 is a view showing some steps of a method of manufacturing the holding lid of FIG. 6;

FIG. 8 is an explanatory view of a main step following FIG. 7;

FIG. 9 is a view showing a holding lid used in a method of another embodiment of the present invention.

FIG. 10 is a view showing an outer mold used in a method of another embodiment of the present invention.

FIG. 11 is a comparative example diagram shown as a comparative example for explaining advantages of the outer mold of FIG. 2;

FIG. 12 is a comparative example shown as a comparative example for explaining advantages of the method of the embodiment shown in FIG. 5;

FIG. 13 is a view showing an example of a conventional method for manufacturing a curved hose.

FIG. 14 is a diagram showing an example of a conventional method of manufacturing a curved hose different from FIG.

[Explanation of symbols]

 10, 76, 82 Curved hose 10A Unvulcanized rubber hose 12 First bent portion 14 Second bent portion 22, 74, 78 Outer die 24 Molding groove portion 36 Groove bottom surface 38 Groove side surface 40 Opening 42 Holding lid 43, 60, 72 Pressing surface 80 Curved portion 84 Molded concave portion

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI // B29K 21:00 105: 24 B29L 23:00

Claims (5)

[Claims] 1. An unvulcanized rubber hose is radially fitted through an opening of the molding groove along the molding groove of an outer mold having a curved molding groove having a curved portion corresponding to a curved hose product. In the method for manufacturing a curved hose in which the unvulcanized rubber hose is set and held in a bent shape to perform vulcanization, at least a part of the molding groove portion is an inner peripheral side of the bent portion as the outer die. A method having a shape having the opening along the outer periphery and having a groove bottom along the outer peripheral side. 2. An unvulcanized rubber hose is radially fitted through an opening of the molding groove along the molding groove of an outer mold having a curved molding groove having a curved portion corresponding to a curved hose product. In a method of manufacturing a curved hose in which the unvulcanized rubber hose is vulcanized while being held and constrained in a curved shape, a presser lid having a presser surface facing a bottom surface of the molding groove is attached to the outer mold. By hitting the bent portion of the unvulcanized rubber hose fitted and set to the exposed portion of the opening of the forming groove, while suppressing deformation of the bent portion in the projecting direction from the forming groove,
A method for producing a curved hose, comprising vulcanizing the unvulcanized rubber hose. 3. The outer mold according to claim 2, wherein, as the outer mold, the forming groove has first and second bent portions corresponding to the curved hose product, and the first and second bent portions are formed. The curved grooves are formed in different planes forming a predetermined angle, and the molding grooves are formed in a three-dimensional curved shape as a whole. A method for producing a curved hose, comprising vulcanizing a rubber hose. 4. The unvulcanized rubber hose according to claim 1, wherein the groove depth of the molded groove portion is deeper than the radius of the unvulcanized rubber hose, and the opening width of the opening of the molded groove portion is the unvulcanized rubber hose. A method for producing a curved hose, wherein the hose has a diameter substantially equal to the diameter of the hose. 5. A method of manufacturing a curved hose in which an unvulcanized rubber hose is set in a molding concave portion of an outer mold, held and restrained in a bent shape having a bent portion of a predetermined shape, and vulcanized in that state. As the mold, an outer mold made of a cylindrical pipe having a curved shape corresponding to the bent part and partially restraining the bent part in the longitudinal direction is used, and the unvulcanized rubber is shafted with respect to the outer mold. A part of the unvulcanized rubber hose in the longitudinal direction is held and constrained in a curved shape by inserting the uncured rubber hose in a direction, and vulcanizing treatment is performed in that state.